Field of the Invention
This disclosure relates to apparatus and methods for remote operation of potentially hazardous equipment, such as electrical switches. More particularly, the disclosure provides apparatus and methods for the controlling equipment through remote actuation of a mechanical link, while distancing a human operator from a potential hazard.
Background
It is well understood that industrial equipment includes points of control such as valves and switches that manage very large and potentially dangerous amounts of energy or materials. The vast majority of such control points are operated safely. However, there are some situations, e.g., equipment malfunction, use of equipment outside of rated specifications, or equipment misuse, which can lead to hazardous situations such as explosions, toxic material release, and the like.
For example, in the power distribution industry, personnel who work on or near energized electrical equipment can be seriously injured or killed as a result of arcing faults. An arcing fault is the flow of current through the air between phase conductors and neutral or ground and can result in a tremendous release of energy in the form of extremely high temperatures and pressures along with shrapnel hurling through the air at high velocity. For this reason, when repair work or periodic maintenance needs to be accomplished, the circuit breakers are tripped (opened) and moved out of conductive contact with the primary and secondary disconnects and removed from the switchgear cell. Some circuit breaker switches are rotated with a “hot stick” (insulated rod) while others are operated by hooking the end of a hot stick into a ring connected to a movable contact and pulling or pushing on the ring to open or close the contacts respectively.
More generally, control mechanisms broadly fall into two categories: rotary operation and linear operation. Thus, it is desirable to provide improved apparatus and methods for actuating valves and/or switches at a distance from a user such that improved safety results.